Prions are proteinaceous infections particles free of nucleic acid. Prions are known to cause several brain diseases including kuru, Creutzfeldt-Jakob disease, Gerstmann-Straussler-Scheinker disease, and fatal familial insomnia in humans; scrapie in sheep; bovine spongiform encephalopathy (Mad Cow Disease) in cattle; transmissible mink encephalopathy in mink; chronic wasting disease in deer and elk; and feline spongiform encephalopathy in cats. These diseases lead to symptoms including dementia, ataxia, behavioral disturbances, dizziness, involuntary movement, and death. Prions can be transmitted by exposure to infected tissue and brain tissue, spinal cord tissue, pituitary tissue, and eye tissue in particular.
Prions are difficult to decontaminate using conventional chemical and physical methods. Many traditional chemical disinfectants are ineffective against prions, or have limited efficacy, including alcohol, ammonia, hydrogen peroxide, peracetic acid and boiling. Some traditional chemical and physical disinfectants have been shown to be variably effective including sodium hydroxide, guanidinium isothiocyanate (4M), autoclaving at at least 134° C. for at least one hour, and boiling in 3% sodium dodecyl sulfate.
Research has been ongoing in order to develop an effective method of inactivating prions.